Knob



FIG. 1 is a perspective view of a knob showing my new design;

FIG. 2 is a right side view thereof, the left side, top plan and bottom plan views being substantially identical to the right side view shown;

FIG. 3 is a front view thereof; and,

FIG. 4 is a rear view thereof.

The fastener aperture depicted in broken lines in FIG. 4 is shown for illustrative purposes only and forms no part of the claimed subject matter. 

The ornamental design for a knob, as shown and described. 